1 files changed, 87 insertions, 69 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index a479b63112ea..27f3716bdc1f 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -22,6 +22,7 @@
  */
 
 #include <linux/debugfs.h>
+#include <linux/iopoll.h>
 
 #include <drm/display/drm_dp_helper.h>
 #include <drm/drm_print.h>
@@ -478,12 +479,13 @@ static u8 intel_dp_get_lane_adjust_train(struct intel_dp *intel_dp,
 	_TRAIN_REQ_TX_FFE_ARGS(link_status, 2), \
 	_TRAIN_REQ_TX_FFE_ARGS(link_status, 3)
 
-void
+bool
 intel_dp_get_adjust_train(struct intel_dp *intel_dp,
 			  const struct intel_crtc_state *crtc_state,
 			  enum drm_dp_phy dp_phy,
 			  const u8 link_status[DP_LINK_STATUS_SIZE])
 {
+	bool changed = false;
 	int lane;
 
 	if (intel_dp_is_uhbr(crtc_state)) {
@@ -502,10 +504,17 @@ intel_dp_get_adjust_train(struct intel_dp *intel_dp,
 		       TRAIN_REQ_PREEMPH_ARGS(link_status));
 	}
 
-	for (lane = 0; lane < 4; lane++)
-		intel_dp->train_set[lane] =
-			intel_dp_get_lane_adjust_train(intel_dp, crtc_state,
-						       dp_phy, link_status, lane);
+	for (lane = 0; lane < 4; lane++) {
+		u8 new = intel_dp_get_lane_adjust_train(intel_dp, crtc_state,
+							dp_phy, link_status, lane);
+		if (intel_dp->train_set[lane] == new)
+			continue;
+
+		intel_dp->train_set[lane] = new;
+		changed = true;
+	}
+
+	return changed;
 }
 
 static int intel_dp_training_pattern_set_reg(struct intel_dp *intel_dp,
@@ -758,6 +767,63 @@ void intel_dp_link_training_set_bw(struct intel_dp *intel_dp,
 	}
 }
 
+/*
+ * Pick Training Pattern Sequence (TPS) for channel equalization. 128b/132b TPS2
+ * for UHBR+, TPS4 for HBR3 or for 1.4 devices that support it, TPS3 for HBR2 or
+ * 1.2 devices that support it, TPS2 otherwise.
+ */
+static u32 intel_dp_training_pattern(struct intel_dp *intel_dp,
+				     const struct intel_crtc_state *crtc_state,
+				     enum drm_dp_phy dp_phy)
+{
+	struct intel_display *display = to_intel_display(intel_dp);
+	bool source_tps3, sink_tps3, source_tps4, sink_tps4;
+
+	/* UHBR+ use separate 128b/132b TPS2 */
+	if (intel_dp_is_uhbr(crtc_state))
+		return DP_TRAINING_PATTERN_2;
+
+	/*
+	 * TPS4 support is mandatory for all downstream devices that
+	 * support HBR3. There are no known eDP panels that support
+	 * TPS4 as of Feb 2018 as per VESA eDP_v1.4b_E1 specification.
+	 * LTTPRs must support TPS4.
+	 */
+	source_tps4 = intel_dp_source_supports_tps4(display);
+	sink_tps4 = dp_phy != DP_PHY_DPRX ||
+		    drm_dp_tps4_supported(intel_dp->dpcd);
+	if (source_tps4 && sink_tps4) {
+		return DP_TRAINING_PATTERN_4;
+	} else if (crtc_state->port_clock == 810000) {
+		if (!source_tps4)
+			lt_dbg(intel_dp, dp_phy,
+			       "8.1 Gbps link rate without source TPS4 support\n");
+		if (!sink_tps4)
+			lt_dbg(intel_dp, dp_phy,
+			       "8.1 Gbps link rate without sink TPS4 support\n");
+	}
+
+	/*
+	 * TPS3 support is mandatory for downstream devices that
+	 * support HBR2. However, not all sinks follow the spec.
+	 */
+	source_tps3 = intel_dp_source_supports_tps3(display);
+	sink_tps3 = dp_phy != DP_PHY_DPRX ||
+		    drm_dp_tps3_supported(intel_dp->dpcd);
+	if (source_tps3 && sink_tps3) {
+		return  DP_TRAINING_PATTERN_3;
+	} else if (crtc_state->port_clock >= 540000) {
+		if (!source_tps3)
+			lt_dbg(intel_dp, dp_phy,
+			       ">=5.4/6.48 Gbps link rate without source TPS3 support\n");
+		if (!sink_tps3)
+			lt_dbg(intel_dp, dp_phy,
+			       ">=5.4/6.48 Gbps link rate without sink TPS3 support\n");
+	}
+
+	return DP_TRAINING_PATTERN_2;
+}
+
 static void intel_dp_update_link_bw_set(struct intel_dp *intel_dp,
 					const struct intel_crtc_state *crtc_state,
 					u8 link_bw, u8 rate_select)
@@ -950,63 +1016,6 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp,
 }
 
 /*
- * Pick Training Pattern Sequence (TPS) for channel equalization. 128b/132b TPS2
- * for UHBR+, TPS4 for HBR3 or for 1.4 devices that support it, TPS3 for HBR2 or
- * 1.2 devices that support it, TPS2 otherwise.
- */
-static u32 intel_dp_training_pattern(struct intel_dp *intel_dp,
-				     const struct intel_crtc_state *crtc_state,
-				     enum drm_dp_phy dp_phy)
-{
-	struct intel_display *display = to_intel_display(intel_dp);
-	bool source_tps3, sink_tps3, source_tps4, sink_tps4;
-
-	/* UHBR+ use separate 128b/132b TPS2 */
-	if (intel_dp_is_uhbr(crtc_state))
-		return DP_TRAINING_PATTERN_2;
-
-	/*
-	 * TPS4 support is mandatory for all downstream devices that
-	 * support HBR3. There are no known eDP panels that support
-	 * TPS4 as of Feb 2018 as per VESA eDP_v1.4b_E1 specification.
-	 * LTTPRs must support TPS4.
-	 */
-	source_tps4 = intel_dp_source_supports_tps4(display);
-	sink_tps4 = dp_phy != DP_PHY_DPRX ||
-		    drm_dp_tps4_supported(intel_dp->dpcd);
-	if (source_tps4 && sink_tps4) {
-		return DP_TRAINING_PATTERN_4;
-	} else if (crtc_state->port_clock == 810000) {
-		if (!source_tps4)
-			lt_dbg(intel_dp, dp_phy,
-			       "8.1 Gbps link rate without source TPS4 support\n");
-		if (!sink_tps4)
-			lt_dbg(intel_dp, dp_phy,
-			       "8.1 Gbps link rate without sink TPS4 support\n");
-	}
-
-	/*
-	 * TPS3 support is mandatory for downstream devices that
-	 * support HBR2. However, not all sinks follow the spec.
-	 */
-	source_tps3 = intel_dp_source_supports_tps3(display);
-	sink_tps3 = dp_phy != DP_PHY_DPRX ||
-		    drm_dp_tps3_supported(intel_dp->dpcd);
-	if (source_tps3 && sink_tps3) {
-		return  DP_TRAINING_PATTERN_3;
-	} else if (crtc_state->port_clock >= 540000) {
-		if (!source_tps3)
-			lt_dbg(intel_dp, dp_phy,
-			       ">=5.4/6.48 Gbps link rate without source TPS3 support\n");
-		if (!sink_tps3)
-			lt_dbg(intel_dp, dp_phy,
-			       ">=5.4/6.48 Gbps link rate without sink TPS3 support\n");
-	}
-
-	return DP_TRAINING_PATTERN_2;
-}
-
-/*
  * Perform the link training channel equalization phase on the given DP PHY
  * using one of training pattern 2, 3 or 4 depending on the source and
  * sink capabilities.
@@ -1127,16 +1136,19 @@ void intel_dp_stop_link_train(struct intel_dp *intel_dp,
 {
 	struct intel_display *display = to_intel_display(intel_dp);
 	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
+	int ret;
 
 	intel_dp->link.active = true;
 
-	intel_dp_disable_dpcd_training_pattern(intel_dp, DP_PHY_DPRX);
 	intel_dp_program_link_training_pattern(intel_dp, crtc_state, DP_PHY_DPRX,
 					       DP_TRAINING_PATTERN_DISABLE);
 
-	if (intel_dp_is_uhbr(crtc_state) &&
-	    wait_for(intel_dp_128b132b_intra_hop(intel_dp, crtc_state) == 0, 500)) {
-		lt_dbg(intel_dp, DP_PHY_DPRX, "128b/132b intra-hop not clearing\n");
+	if (intel_dp_is_uhbr(crtc_state)) {
+		ret = poll_timeout_us(ret = intel_dp_128b132b_intra_hop(intel_dp, crtc_state),
+				      ret == 0,
+				      500, 500 * 1000, false);
+		if (ret)
+			lt_dbg(intel_dp, DP_PHY_DPRX, "128b/132b intra-hop not clearing\n");
 	}
 
 	intel_hpd_unblock(encoder);
@@ -1371,8 +1383,8 @@ intel_dp_link_train_all_phys(struct intel_dp *intel_dp,
 	if (ret)
 		ret = intel_dp_link_train_phy(intel_dp, crtc_state, DP_PHY_DPRX);
 
-	if (intel_dp->set_idle_link_train)
-		intel_dp->set_idle_link_train(intel_dp, crtc_state);
+	intel_dp_disable_dpcd_training_pattern(intel_dp, DP_PHY_DPRX);
+	intel_dp->set_idle_link_train(intel_dp, crtc_state);
 
 	return ret;
 }
@@ -1574,8 +1586,12 @@ intel_dp_128b132b_link_train(struct intel_dp *intel_dp,
 			     int lttpr_count)
 {
 	bool passed = false;
+	int ret;
 
-	if (wait_for(intel_dp_128b132b_intra_hop(intel_dp, crtc_state) == 0, 500)) {
+	ret = poll_timeout_us(ret = intel_dp_128b132b_intra_hop(intel_dp, crtc_state),
+			      ret == 0,
+			      500, 500 * 1000, false);
+	if (ret) {
 		lt_err(intel_dp, DP_PHY_DPRX, "128b/132b intra-hop not clear\n");
 		goto out;
 	}
@@ -1602,6 +1618,8 @@ out:
 		intel_dp_program_link_training_pattern(intel_dp, crtc_state,
 						       DP_PHY_DPRX, DP_TRAINING_PATTERN_2);
 
+	intel_dp_disable_dpcd_training_pattern(intel_dp, DP_PHY_DPRX);
+
 	return passed;
 }